A model is proposed and studied describing an infinite population of point migrants arriving in and departing from X ⊆ R d , d ≥ 1. Both these acts occur at random with state-dependent rates. That is, depending on their geometry the existing migrants repel and attract the newcomers, which makes the population a complex system. Its states are probability measures on an appropriate configuration space, and their evolution µ0 → µt is obtained by solving the corresponding Fokker-Planck equation. The main result is the conclusion that this evolution of states preserves their sub-Poissonicity, and hence a local self-regulation (suppression of clustering) takes place due to the inter-particle repulsion -no matter of how small range. Further possibilities to study the proposed model with the help of this result are also discussed.